P1078
P1078, P1084 EVT CONTROL POSITION SENSOR
Description
Exhaust valve timing control position sensor detects the concave groove of the exhaust camshaft rear end.
This sensor signal is used for sensing a position of the exhaust camshaft.
This sensor uses a Hall IC.
Based on the position of the exhaust camshaft, ECM controls exhaust valve timing control magnet retarder to optimize the shut/open timing of exhaust valve for the driving condition.
DTC Logic
DTC DETECTION LOGIC
NOTE:
If DTC P1078 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. P0643.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
- GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and let it idle for 10 seconds.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES - Go to SEE Diagnosis Procedure.
NO - INSPECTION END
Diagnosis Procedure
1.CHECK GROUND CONNECTION
1. Turn ignition switch OFF.
2. Check ground connection M95. Refer to Ground Inspection in Circuit Inspection.
Is the inspection result normal?
YES - GO TO 2.
NO - Repair or replace ground connection.
2.CHECK EXHAUST VALVE TIMING CONTROL POSITION SENSOR POWER SUPPLY CIRCUIT-I
1. Disconnect exhaust valve timing control position sensor harness connector.
2. Turn ignition switch ON.
3. Check the voltage between exhaust valve timing control position sensor harness connector and ground.
Is the inspection result normal?
YES - GO TO 8.
NO-1 - P1078: Repair open circuit or short to ground or short to power in harness or connectors.
NO-2 - P1084: GO TO 3.
3.CHECK EXHAUST VALVE TIMING CONTROL POSITION SENSOR POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between exhaust valve timing control position sensor harness connector and ECM harness connector.
Is the inspection result normal?
YES - GO TO 4.
NO - Repair open circuit.
4.CHECK SENSOR POWER SUPPLY CIRCUIT
Check harness for short to power and short to ground, between the following terminals.
Is the inspection result normal?
YES - GO TO 5.
NO - Repair short to ground or short to power in harness or connectors.
5.CHECK COMPONENTS
Check the following.
- Crankshaft position sensor (POS) ( P0335.)
- Camshaft position sensor (PHASE) (bank 2) ( P0340.)
- Battery current sensor ( P1550.)
- EVAP control system pressure sensor ( P0451.)
- Refrigerant pressure sensor ( Magnetic Clutch.)
Is the inspection result normal?
YES - GO TO 6.
NO - Replace malfunctioning component.
6.CHECK APP SENSOR
P2122.
Is the inspection result normal?
YES - GO TO 14.
NO - GO TO 7.
7.REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly.
2. Go to P2122.
- INSPECTION END
8.CHECK EXHAUST VALVE TIMING CONTROL POSITION SENSOR GROUND CIRCUIT FOR OPEN AND
SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between exhaust valve timing control position sensor harness connector and ECM harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES - GO TO 9.
NO - Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK EXHAUST VALVE TIMING CONTROL POSITION SENSOR INPUT SIGNAL CIRCUIT FOR OPEN
AND SHORT
1. Check the continuity between exhaust valve timing control position sensor harness connector and ECM harness connector.
2. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES - GO TO 10.
NO - Repair open circuit or short to ground or short to power in harness or connectors.
10.CHECK EXHAUST VALVE TIMING CONTROL POSITION SENSOR
SEE Component Inspection.
Is the inspection result normal?
YES - GO TO 11.
NO - Replace malfunctioning exhaust valve timing control position sensor.
11.CHECK CRANKSHAFT POSITION SENSOR (POS)
P0335.
Is the inspection result normal?
YES - GO TO 12.
NO - Replace crankshaft position sensor (POS).
12.CHECK CAMSHAFT POSITION SENSOR (PHASE)
P0340.
Is the inspection result normal?
YES - GO TO 13.
NO - Replace malfunctioning camshaft position sensor (PHASE).
13.CHECK CAMSHAFT (EXH)
Check the following;
- Accumulation of debris to the signal plate of camshaft rear end
- Chipping signal plate of camshaft rear end
Is the inspection result normal?
YES - GO TO 14.
NO - Remove debris and clean the signal plate of camshaft rear end or replace camshaft.
14.CHECK INTERMITTENT INCIDENT
Intermittent Incident.
- INSPECTION END
Component Inspection
1.EXHAUST VALVE TIMING CONTROL POSITION SENSOR-I
1. Turn ignition switch OFF.
2. Disconnect exhaust valve timing control position sensor harness connector.
3. Loosen the fixing bolt of the sensor.
4. Remove the sensor.
5. Visually check the sensor for chipping.
Is the inspection result normal?
YES - GO TO 2.
NO - Replace malfunctioning exhaust valve timing control position sensor.
2.EXHAUST VALVE TIMING CONTROL POSITION SENSOR-II
Check resistance exhaust valve timing control position sensor terminals as shown below.
Is the inspection result normal?
YES - INSPECTION END
NO - Replace malfunctioning exhaust valve timing control position sensor.